Method and apparatus for grouting concrete structures



l 1,726,414 METHOD AND APPARATUS FOR GROUTING CONCRETE STRUCTURS l 1. L.sAvAG Aug. 27, 1929.

- 5 Shets-Sheet Filed Jan. 16, 1928 u uw...

Aug. 27, 1929.

J. SAVAGE 1,726,414

AND APPARATUS FOR G'ROUTINGv CONCRETE STRUCTURES METHOD led dan 1928 3Sheets-SheetA @HHHHH Hu:

, .n.HHHHHhH@ n Aug. 27, 1929. I .1. 1 SAVAGE 1,726,414

v METHOD AND APPARATUS FOR GROUTING CONCRETE STRUCTURES Filed Jan. 16,1928' 3 Sheets-Sheet 5 dm mdf, formy;

Patented A ug( 27, 1929.

Jona L. savaenor nnnvnn., comme.

Application led Inmary 16,'.1928- Serial No. 247,045Q

lMy invention relates to new system' and apparatus for introducingsuitable grouting material into contraction joints or constructionjoints of concrete structures 41n the cours'eof their erection, or,after their com pletion', and to avoid the attendant ditiicul ties,uncertainties, and'v heavy expense which the use of the methodsandequipment at present available'entail. i

. It is wellknown to art that v'concrete contracts in setting andparticularly when subjected to low temperatures and that any longconcrete structure will develop transverse cracks at frequentintervalsthroughout its length as a` result of this contraction.: It is possibleto controltlie location and extent of these contraction cracks byproviding frequent. jointsin the concrete which in the terminology oftheart arecalled construction joints. or preterably contraction joints.While these contraction joints are necessary and desirable for thepurpose of pre-determining the location and direction of the contractioncracksl they introduce planes of weakness through Ythe concretestructure which are undesirable Afor structural reasons as compared witha j monolithic structure. In order to minimize this structural defectand'to strengthen these planes of weakness it has'beqome the practice ofengineers to require thatall contraction joints in important concretedams and other massive structures be filled under pressure with Portlandcement grout or other cementingmateriah' at' -a time when the structureis at the -lowest temperature 'and the contraction joints have themaximum opening. By this means the separate -parts or units ofthestructure are cemented together,',orming `practically a' monolithicstructure. The grouting of vertical contraction joints in this manner is`of particular importance in the case ot concrete arch vdamswhere `it isessential to fill the joints with a strong grouting material in order toforma continuous arch cylinder to receivev `tl1e arch thrust, andtransmit it into the'l canyon walls throughthe abutments at each end ofthe dam.

Inorder that all'contraction joints in a concrete structure may be-illedup in such a manner that the t'wof closely adjoining parts or units maybe bonded integrally together, some lcontinuously connected conduitsystem must be'pro'vided that will form the passageway thpse skilled inai@ by which the cementing,L fluidl or grout can be dischargedunderpressure 4 i'nto the" contraction joints between each adjolnlng' pair"of concrete units.

My inventi'orrcontemplates in the accomplishment fof-these results theuse of any lsystem of operative procedure, and any arrangement of pipesor -conduits that are embedded in the body of the concrete at a distancefar enough back from the formed face to provide convenient and rigidattachment to the forms and to insure their proper protection by`embedment in the concrete, and any system or 'arrangement of pipes,which provide closed conduits for leading the ceinenting iuid or 'groutto predetermined -1 points along the'contraction joint-betweendltl'erent units of a concrete structure.

In'the accompanying sheets of drawings I have illustrated my inventionapplied to a'large dam, butit will be understood that the specific formof its application as herein illustrated is illustrative of theprinciple of the invention, and is capable of being varied 'to suit thetype of. structure in which vit is.

to be employed or utilized.

The objects' of my invention are:

First; to providea conduit systemv and i apparatus 'for gronting theconstruction joints orcontraction joints which will occurV betweendifferent parts of a concrete structure. of large dimenslons such as amassive concretedam or retaining wall 11i-which one or more parts orunits ofl the structure are built up progressively to partial or fullheight and allowed to harden in advance' of the other arts or units .ofthe structure which are': ater poured against the formed Afaces ofthepartsor units vfirst built;

j Second; Vto provide a conduit system and apparatus for 'grouting'concrete structures whereby the shrinkage and temperature cracksdeveloping between the .different parts or -unitsof the structure, whichhave been poured at different times, are grouted under pressure` withcement grout and strongly bonded to form them into one integral whole.

Third; to provide a simple, inexpensive, easily erected groutingsystemof suiicently rigid construction to remain in place while the concretestructure is; being poured and Vwhich will be eiective lin thoroughlyfilling all contraction joints when the pressure groutin operation isperformed.

Fourt to-provide a conduit supplying, distributing and introducingsystem and apparatus which can' be progressively installed unit by unitas the forms for each successive vertical increment of a large concreteunit are erected upon and above the concrete previously poured andseasoning, and thereby avoiding any necessity of following any specialerection and construction programs from'those which would be followedwere a grouting mechanism not used.y

Fifth; to provide a plurality of conduits communicating independentlybetween predeterminedly positioned points of entry into the space to begrouted or filled, and the outside source of supply where the groutingmaterial is introduced under pressure, with said plurality ofcommunicating conduits entirely embedded and contained within theconcrete first poured and seasoned, and thereby effectually protectedfrom injury during the period of construction of the adjacent concreteunits on either side.

I attain these objects by the mechanism I and systemillustratedin theaccompanying drawings, in which:

Figure 1 is a vertical sectional view, showing a fragment of the woodform or lagging for confining a unit or part of the concrete structure,in connection with a grout supplying header pipe (l), a riser pipe (2),a horizontal nipple (6), and a conduit outlet box (7) through whichgrout is forcedinto the contraction joint.

Figure `2 is a vertical sectional view -of a portion of a finishedvconcrete unit, showing the embedded grout supplying pipes and conduitoutlet box and a similar conduit outlet box secured on the embeddedoutlet box. Figure 3 is a vertical sectional view through' portions oftwo finished and hardened concrete units, showing the contraction joint(26), between the units, and the separated conduit. outlet boxes throughwhich the grout can flow froml the supply pipes to the contractionjoints.

Figure 4 is a front view of'one of the con-4 duit outlet boxes.

Figure 5 is a side .view partlyin section of a structural concrete unit,showing the grout supplying header pipe (l), embedded therein, the riserpipes l(2), connected therewith and the conduit outlet boxes (7) whichare connected by short pipes or nipples (6) with the riser pipes', theunit having the appearance it presents when ready .for the pouring of anadjoining unit or part ofthe concrete structure. r

4Figures 6 and 7 vare plan Niews of two wooden forms confining twovconcrete. units or parts of the concretestiucture, showing the embeddedgrout' conveying pipes connected to the forms, the two units beingseparated by a space to receive a third unit after the first and secondunits have hardened.

Figure 7A is a plan view of a fragment of one of the concrete units,`showing the con-- figuration of one-of the side faces thereof.'

Figure 8 is an end view showing the manner of connecting the two sets ofriser pipes with a common header pipe.

Figure 9 is a plan view of a fragment of 7 a concrete-holding form,showing a metal strip secured to one side thereof'which later closes thecontraction gap between two adjoining concrete units.

Figure l() is a plan view of a portion of 7 a hardenedXinit, and thegap-closing strip partially em edded therein. Figure 11 is a plan viewof fragments of two hardened units, showing the contraction gap betweenthem, and the gap-closing strip 8 partially embedded in each unit; and

Figure l2 is a side view, showing the upper portion of the unitillustrated in Figure 5.

Referring now to the drawings the-appa- 5 ratus I employ to accomplishthe ob-jects of my invention consists of a header pipe 1,' which isplaced horizontally or approximately so at the lower confines or bottomedge portion of each of the contraction lagging form A, which will bethe faceof the concrete unit or block of concrete alongwhich thevcontraction joint is to occur to the top surface of the completedstructure. i l

In the preferred construction of the header and riser pipes l, 2, and 2Arespectively, the header pipe .is preferably l inch in diameter andriser pipes are preferably onehalf inch in diameter, and are made of anyl predetermined length, and the sections are connected by 'Ts 5 and 5Arespectively. To the Ts 5, are threaded nipples 6, which projecthorizontally from the Ts, and to the outer end of each nipple 6 issecured a dish shaped cup 7, that is provided with a circular flange 8,and the cup 7 is'adjustably secured on the end of the nipple 6 by locknuts 23 and 24, as this arrangement allows the cup to be adjusted on thenipple 6, so

that the face 8, of its flange, can be screwed up tight against theinside surface of the inner face 8 of the form A.

My invention contemplates the securing of the flange 8, of the cup upagainst the inside face 3, of the form A, by any suitable means; but Ipreferably secure it tothe inside face of the form with nails or similarsuitableattachments substantially as shown in the accompanying drawingat B. I pref'- erably have the vertical riser pipes 2 and 2A made in anumber of units whose equal lengths each is slightly shorter than thedesired -vertical distance between the horizontally-positioned nipples 6'that communl cate with the dish or cup pieces 7 and 7A which arefastened to the inner face 3 of the walls of the forms A and theiropposing ends are attached to the horizontal nipples'6, whose oppositeends are screwed into `reach the final completed height of the strucx Inaddition to the support afo'rded ture. the vertical riser 2 by thehorizontal nipple 6 connecting to the cup or dished piece 7 ,I

place a double wire 11 around the riser pipe' 2, above the T 5, and passthese wires through the wall of the form A, and tie their protrudingends firmly together. I then insert a suitable nail 12 or bar. throughthe parallel pair of wires about midway between the form and the riserpipe and by turning-the nail or bar in a plane at right angles to thecommonaxis of the wires, twist the wires around each other tightly, andthis twisting causes 'atension to exist in the wires, which pullsagainst the riser pipes, and this .pull is resisted by the .horizontalnipple 6, connecting the riser 2 to the cupped dish pieces 7 against theinside surface 3 of the wall of the form A, so that by means of thecupped piece 7, with its horizontal nipple 6, connecting it to the riserpipe 2, and the twisted wires 11 ypulling against this horizontal thrustresisting nipplel member 6, and the similar treatment of the other likeunits lin the same manner, make andcom- .prise a strong rigid structurefor the purpose intended, which can be built up readily as fast astheforms are erected, and 'will re- -main fixed in the predeterminedlyselected and4 erected positions while `the concrete is poured intothe-completed forms and thereafter as well. The header pipes I, are madeup of sec-tions of pipe connected by T couplings 1A, the alternate Tcouplings having their center openings pointlng outward, andA to theselattep couplings are connected relatively short horizontal pipes 9, tothe outer ends of which are attached either T couplings or elbows 9A,the elbows being shown in Figure 8, and to the elbows are connected theriser pipes 2A, made up of pipe sections ,and T couplings 5A, and tothese couplings are connected nipples 6A to .which are connected flangedcups 7A similar to the cups 7 on'the nipples 6. The risers 2A are aboutnine inches to the outside of the risers 2,' and the cups 7A alternatewith respectto the ositions of the cups 7 as clearly shown in Figure 5.The purpose of the double row of risers, will hereinafter appear.

.Two header pipes 1 extend along the opposite sides of veach unit 'ofconcrete to be made as shown in the plan view Figure 6, and a largenumber of riser ipes 2 and 2A, are connected `to the top of t esetwoheader pipes 1, and to the horizontal pipes 9 respec-` tively, and areplaced at any predetermined distance apart. Both ofthe header pipes andall of the. riser pipes 2 and 2A, are installed inside of the forms A,as soon as they are erected, for those units of the-structure which areto be pouredl first, and are positioned a reasonable distance back fromthe face 3y of the form A which produces ,y

the contraction joint face, so that whenvthe forms A are filled withconcrete, the header pipes 1, and the riser pipes'2 and 2A, arecompletely surrounded and embedded within the concrete.

orm its border outline along its sides into n a continuous succession ofcorrugations 12A, the surface ofv each of which is preferably e ual inlength, that is, the flat `straight sur ace 13 of the projectingportions of the corrugation are equal in ngth to the length of the flatstraight surface 14 of the recessed portions of the corrugations, asshown in Figure 7, and this outline vof the border or boundary of eachunit necessitates that thevform A be also built in this In lafying out aunit of concrete, I prefl erably corrugated outline and in itsconstruction vertical posts 15 or studding is pl'aced'at thekintersecting of the parts of the form'A f f at its inside corners 16,and atthose vertical end portions 17 of the formA A, which prescribe theopposite outside 5 edges of the contraction joint in-'a vertical plane.I insert lbands of metal 18 or otherY suitable material having V-shapedfolds 18-A along the central portion of. their widths, with their foldedportion resting against the contracting joint forming faces of the formswhich in this case would be lthe outside surface of the form A, the purose of these bands being to form a stop which will later prevent thegrout from escaping from along the contraction` joint faces at theopposite corners 19 ofthe entire height of the unit.

The corrugations 13` and 14 in the form A, ofthe concrete units G and Hof Figures 6 and7 that are opposite to each other form a continuoustongue and groove surface throughout practically their entire length;

and assuming that these two units G and H which aredefined by theopposite forms Ky and K1 of the unit G, and the opposite sides L and L1of the form IjI, have been vpoured and have hardened, then by closing upthe opposite ends M and M1 of the space N, this space or unit N can bepoured, and when iso it is poured the concrete flows into the verticalgroove members against the surfaces 14, that define the depth of thesegrooves; and this tongue and .groove construction of new units betweenhardened units results in thenew units being rigidly locked4 by thesenumerous tonguelike keys that enter the hardened units, against anypossible movement whatever from down steam pressures that would fiowagainst its upsteam end, asl the units in dam construction are placedtransversely across the length of the dam, but the units can be arrangedin any other predetermined positions relative tol the length and breadthof other kinds of concrete work. v

After the concrete has been poured and has set, the forms are removed inthe usual manner, and the form facing portions of the cup-shaped dishedpieces are then exposed withv their flanged edges flush with the surfaceof the concrete and the ends of the nails which held and secured them tothe forms are now left protruding from the concrete.

I now place another set of cups 19A, that are also provided with flanges20Ath-at are identical in shape and size with those cups 7 that are nowembedded in the concrete, against the faces of their flanges 8, and` bybending the protruding ends 21 of the nails B over the peripheral edgeof this opposing cup member 19A, I secure them firmly in place againstthe cup pieces 7 carried by the concrete as shown in Figure 2.

Into the middle diameter or central portion of each of this second setof cup ieces, Il place or inse'rt a pipe nipple 22 into a threaded orunthreaded hole in the center of the cup piece provided for thatpurpose, and secure the nipple 22 by screwing a locking nut 23 againstthe outside surface of the cup piece 19A, and in case the hole isunthreaded a similar nut 24, see Figure 4, can be screwed onto the endofthe nipple 22 against ,the opposite inside surface of the cup piece aswell. On the outer end of this pipe nipple 22, I screw a cap 25 to closeits open end. This protruding nipple 22 with its cap 25 forms ananchorage for their cup piece19A to rigidly secure. it in the concretewhich will later be poured around it.

After each of the fiush embedded. cup

v pieces 7 in the concrete first poured has had attached to it itsopposingmating cup piece 19A, with its anchoring nipple 22 and cap 25,the concrete can then be poured as soon as the side forms, for thisad]acent unit are erected and are connected to the concrete unitsoneither side already poured.

When this adjacent connecting concrete -m'ass is first poured and whilestill in its workable semi-liquid and plastic condition,

' it is in intimate contact with the contraction joint faces oftheseasoned concrete on either enters into its final stages thistemperature becomes less and less, and the drop in temperature producesa reduction in its mass and its physical dimensions, thus causing itsouter confines to contract towards its center and those portionsoriginally in contact with "5 the mating face portions of the completedstructure first poured on either side recedes from those faces, leavingan aperture or crack 26 between them and inasmuch as the cup pieces lastplaced with their nipples 22 and caps 25 are firmly anchored by thesenipples and caps in this new contracting concrete, they also recede backfrom the flanged faces 8 of the cup pieces 7 embedded in the concretefirst poured, so that'this receding movement produces a gap between thefaces of the mating cup pieces 7 and 19A, in the concrete unit CU1 firstpoured and those i the 'concrete unit CU2 last poured.

When this receding movement between the mating cup pieces occurs, it isresisted only by thel bent nails 21 over their mating flanged edges, andthese nails B consequently n are straightened ,sufficiently bythezrelative movement of the mating edges, as shown in Figure 3 toaccommodate this movement.

In Figure 1, I illustrate a complete uid grout conveying unit set upwithin a form A and at a short but predetermined distance from it andwith its cup member 7 securedl to the inside face of the form A by thenails.

The cup member 7 is illustrated, adjustably mounted on the outer'end ofthe horizontal pipe member 6 or 6A. by means of the c heck nuts;consequently it can be forced tightly up against the inside surface ofthe form A bythevoutside check nut, and then the nails are driven intothe form and then bent down over the eripheral edge of the flange 8.ofthe cup i), and then the double wire 11 is applied to still further drawthe top portion of the upper riser pipentowards the form, and then afterthe vertical part of the piping and the cup have been completely andproperly adjusted, this unit would appear as illustrated in Figure 2.Then the next step is to secure the 4cu member 19A to the face of thecup member and as above described, and then our this t second unit withconcrete, which after hard-` 120 ening having yreceded from thatpreviously poured, then presents the conditionas-showm in Figure 3,which isl now ready to receivei the'. grouting material between the 'twomasses of concrete, which is accomplished by pumping the grout into theheader pipe 1 and forcing it into and between the two oppositely opposedbut now slightly separated cups 7 and 19A, through the opening 27between which the grout is forced' throughout 130 and the two masses orunits of concrete are now integrally united into one monolithic block ofconcrete. In the construction of high dams, the units of concrete are solofty hardened and the uuits that are poured afterthat they have to bebuilt up to'their final height by a number of successive pourings, oneupon one another; consequently there are horizontal joints between theunits as well as the vertical contraction cracks that occur betweenthose units that have set and Wards against their sides, and inextending the riser pipes from their header pipes vertically upwardvthrough a high unit, I preferablyplace the cup members 8 feet apart, asillustrated lin Figure 5, which enables form erection and the successivevertical pourings of the unit until its final height is achieved to beperformed in an easy and simple manner, insuring that, by thus makingthe grouting system of vertical increments of equal length, it can beinserted within and fastened to the-forms as. fast as they are erected,and attached to the system in lace below, contained in theconcrete alrady poured and seasoning. t

`When` the entire concrete structure has I been completed, I haveprovided direct communication from thef'commo'n header pipe 1, which Ihave placed in a parallel position to the bottom portion of eachcontraction crack 26, see Figures 3 and 6,. through the vertical risers2 and 2A, and the horizontal v nipples 6 to the aperture 26 between eachof the flanged edges of the opposing cup pieces 7- and 19A into thecontraction joints or cracks 26, see Figure `3, separating the dfferentconcrete masses CU1 and 2, comprising the completed units, and thesecommunicating points are all predetermined, and exactly positioned, atintervals both vertically and horizontally, suiciently close as toinsure that when the grouting material is introduced under pressurefrom'the exposed ends of the common headers at the bottommost portionsof those contraction 'oint apertures, thats-asI this grouting me iumrises from' the lower portions towards the top portions of thestructure, lit drivesoutthe air before its advance, through-the to vofthe 'aperture and the'exposed open en sfof the riser pipes carried tothe top of the structure for that purpose, illing every portion ofthejoint voids in its upward course and'finallyv appearing at the-top ofthe joints and beginning to overflow from the to s 'ofthe riser pipes,which are progressive y capped. ,off to prevent escape of the groutuntil the highest ones are reached,at which stage the pumping of groutrinto the bottom concrete ture, an that which is poured later, ashereheader .pipe is discontinued, the header.

plugged, and that particular joint is then invention in the forms withreference to that i oured in the first units of the strucin described,that this can readily be done,

j and -in so doing will in no Way depart from the spirit, import andintent of my invention.

The same procedure of pumping grouting media of any suitable materialunder pressure into the bottom header pipes of each of the remainingjoints in turn until cach system has been entirely iilled progressivelyfrom the bottom to the top is followed until all the joints are grouted.The work of grouting can be performed at any time after the concrete hashardened upon both sides of the joint or joints, but the best resultsare obtained when the concrete has a temperature below normal and hasattained maximum contraction as in the winter.

- When Vusing cement grout, I preferably pump each space that forms thelcontraction crack v26, full of clear water before= starting tointroduce the grout, as this meistens allsurfaces which the grout isrequired to bond, and insures that the grout will reach all portions ofthe voids in the crack with its proper free flowing consistency,v whichit would not otherwise retain were it progressively coming in contactwith dry concrete and losing its moisture content by absorption therein.A

While IV have throughout the foregoing descriptionreferred to thecontraction crack apertures as bein in a vertical plane, my v inventionContemp ates a similar and equally efficient use on those which may berequired on otherl than vertical planes as well, and I accordinglyinclude these contraction crack a ertures which are often required andpro'- vlded in other than vertical planes, as being within the 'spiritand intention of this application. v l

In the operation of `my system and apparatus for closing the contractioncracks formed in concrete units while erecting them, the great value andthe advantages of my arrangement and construction are:

That the filling or bonding-mixture is introduced into .the joint atpredetermined separate pointsprogressively fronrthe botbonding could,nototherwise occur, that tlTe conduit system supplying thepredetermined. points of entry-into the joint is entirely removed fromand'fseparate .from and independent of the 'oint aperture, therebymaking certain the delivery ofv thebondin mixture to the -predeterminedpoints o entry into the joint aperture, that the size and cubicalcontent capacity of the elements comprising my invention are materiallyless than any other similar invention now in use', andthis consequentreduction in the amount of grouting medium required to fill my elementspermits the grouting' tol be accomj plished in a shorter space of timeas less grout is required, land this time saving is` of greatimportance, as it is essential that all the grout be in place before itssettin and hardening cycle commences; that the eaders, and verticalrlsers can be and are made from standard products obtainable from.

stocks and purchasable anywhere in the open market, that their size andpoints of interconnection can be varied at .will to fit each.

' by o taining special connections from a. re-

mote and possibly sin le source of supply are eliminated; that t e easeand celerity with which the various units can be assembled and installedin the forms is increased; and that the total` expenditure of moneysrequired for attaining the desired result is greatl lessened; and thatthe results so attaine are superior and preferable tothat of any otherarrangement now in use.

My invention provides an inexpensive system .and apparatus for.constructing and grouti concrete structures, as.all of the l materia sI employ can be obtained at supply houses, and all of the materials Iuse can be quickly erected-in position to receive the concrete, andwhile I have illustrated and described the preferred construction andarrangement of my system and .apparatus for construction and groutingconcrete. structures I do not wish to be limited to the construction andarrangement shown, as changes may be made in it without departing fromthe spirit of my invention. l

Having described my invention what I claim as new and desire to secureby Letters Patent is: l

1. Apparatus for grouting the contraction joint between twoconcreteunits, comprising a header and distributer pipes located in the space inwhich one unitis to be poured, means fixed to the ends of the respectivedistributer pipes and yieldingly secured e,to the forms defining thecontraction joint face of the first unit to prevent concrete fromentering the distributer pipes during pouring of the said unit,individual covers and means for yieldingly securing the same to therespective means on said distributer pipes after pouring of `the saidunit and removal of the forms, and means associated with said covers forfixing the same in .the other concrete unit.

2. The invention as set forth in claim 1',

wherein the said means in the distributer pipes comprise cup-shapedelements having their outerv open ends contacting with the said forms.

3. Apparatus for grouting the contraction joint between two concreteunits, comprising a header and a plurality of distributer pipes,fittings on the ends of said pipes and having flanges abutting againstthe forms defining the contractionV joint face of the unit in which saidpipes are embedded, covers yieldingly secured against the said flangedfittings to close said pipes, and means anchoring said covers in thesecond unit.

4. In apparatus for grouting the contraction joint between two concreteunits, the combination with means embedded in the first unit anddefining a header in the base p ortion of said first unit, verticalchannels rlslng from sald header, and a plurality of horizontal channels-branching from said vertlcal channels and terminating flush with thejointface of said first unit, of individual closures `for each of saidbranch channels, said closures being yieldingly secured to the firstunit after stripping the forms therefrom, and means on said closures forsecurely anchoring .the same .in the second unit.

5'. In apparatus for grouting the contractionv joint between twoconcrete units, the combination with. a verticalpipe in the first unitand spaced from the joint face thereof,

a plurality of branch pipes exten-ding from said vertical pipev towardssaid joint face, and flanged means on said branch pipes prol ll5 vidinga temporary closure :forsaid branch f plpes during pouring of the firstunit, oi?

covers for'- cooperating with said flanged means after stripping of theforms from the first unit to close said branch pipes during pouring ofthe second unit, means for yieldmgly ai'xing said covers to therespective flanged means, and means for anchoring said covers 1n thesecond un1t.

`6. In apparatus for grouting a contraction 'oint between two concreteunits, the l combination with a grout distributing pi e terminatingadjacent the form defining t e joint face of the rst unit, a flangedfitting iao on said pipe and engaging the form to close the end of saidpipe,` and nails partially driven into said form and having their outerportions bent toward said ianged means to second unit, the nail endsexposed by re.

moval of the form constituting means for yieldingly securing said coverto said flanged means.

7. In apparatus for grouting a contraction joint between two concreteunits, the combination of a header Within and adjacent the bottom of thespace in which one unit is to be poured, vertical risers communieatingwith said header, branch pipes extending from 'said risers, flangedmeans on said branch pipes and means yieldingly holding said f iangedmeans in contact with the surface against which said 'concrete unit is'poured. f

8. The invention as set forth in claim 5, wherein said iianged meanscomprise cupshaped elements having peripheral ianges.

9. The invention as set forth in claim 5, wherein said anged means andsaid covers each comprise identical cup-shaped elements havingperipheral flanges.

10. In a concrete construction of the type described, the combinationwith forms defining' the contraction joint face of a massive concreteunit, of means for closing the endet the contraction joint, a header andvertical risersspaced from and positioned by said forms, branch pipesextending from said risers toward said forms, and outlet means on saidbranch pipes and having ianges contacting with said forms to close saidbranch pipes during pouring of thel unit, said flanged means beingpermanently secured to said branch pipes and yieldingly secured to saidforms, whereby upon separation of said forms and the concrete unit, saidbranch pipes are opened into the contraction joint space.

11. The invention as set forth in claim 10, wherein each of said jointclosing means comprlses a metal stripl having lateral wings embedded inthe concrete units and an intermediate Vshaped fold located in the jointspace.

In testimony whereof, I atix my signature.

JOI-IN L. SAVAGE.

